Compare the following complexes with respect to structural shapes of units, magnetic behaviour and hybrid orbitals involved in units :
`[Co(NH_(3))_(6)]^(3+),[Cr(NH_(3))_(6)]^(3+),Ni(CO)_(4)`

Explanation

(i) `[Co(NH_(3))_(6)]^(3+)` Oxidation state of Co= +3
Config. of `Co^(3+)` : `3d^(6)4s^(0)`
Shape : Octahedral
Magnetic behaviour : Diamagnetic
Hybrid orbitals involved : `d^(2)sp^(3)`
(ii) `[Cr(NH_(3))_(6)]^(3+)` Oxidation state of Cr = +3
Configuration of `Cr^(3+)` : `3d^(3)4s^(0)`
Shape : Octahedral
Magnetic behaviour : Paramagnetic
Hybrid orbitals involved : `d^(2)sp^(3)`
(iii) `Ni(CO)_(4)` Oxidation state of Ni = 0
Shape : Tetrahedral
Magnetic behaviour : Diamagnetic
Hybrid orbitals involved : `sp^(3)`